P R E S S R E L E A S E
14 July 2000
CUHK Introduces Quick and Effective Heart Attack Diagnosis Method
- Chronic endocrine disorders
With effective treatment now available for heart attacks, it is very important that we can detect the disease accurately. However, diagnosis of a heart attack at the early stages is not easy. Typically many will have a tight squeezing chest pain but this type of pain can occur with other conditions such as indigestion. More important, many heart attack victims may not have severe pains and some have only a minor discomfort. Even an electrocardiogram (ECG) will only detect about 40-60% of heart attacks.
Chest pain is a very common symptom. Usually, doctors at an A&E department will decide on clinical grounds (symptoms, ECG etc) whether to admit the patients with chest pain complaint and then they have to wait for the results of standard blood test, which means a few-day stay at hospital for observation. Studies in the US and Europe have shown that about 6% of people with a chest pain seen in an A&E department who are sent home because it is thought they do not have a problem with their heart are in fact having a heart attack. These patients have a very high chance of death in the short term (25%) which is at least twice as high if they had been admitted into hospital. Hence, correct diagnosis of chest pain is extremely important both to avoid unnecessary tests and treatments in those who do not have a heart problem and alternatively to make sure those who have had a heart attack get the right treatment, which can be life-saving.
Doctors in the Department of Medicine and Therapeutics, The Chinese University of Hong Kong, in collaboration with their colleagues in the Accident and Emergency department at the Prince of Wales Hospital are now using a new bedside test for heart damage. This allows speedy diagnosis of patients presenting with a suspected acute heart attack or angina. Patients are admitted to dedicated "chest pain unit" beds and a test is done immediately and if negative, repeated in 6-8 hours (see figure). If the repeat test is again negative then the patient can go home. This new "care pathway" can significantly improve management of these patients, reducing the number of days in hospital, the number of clinical investigations and interventions and the cardiovascular drug costs while targeting treatment at those who really need it.
The new bedside test measures the presence in the blood of a constituent of the heart muscle -Troponin T. When the heart is short of oxygen because of a blockage in the feeding artery, the muscle cells become leaky and some of the components inside are released into the blood where they can be detected. Patients who have a negative result i.e. no troponin T in the blood, have a very good prognosis and can be safely discharged home. The new machine that the Chinese University is using needs only a few drops of blood and gives a result in few minutes and can be done at the bedside. With the introduction of this new approach, the average hospital stay per patient was shortened from 7.0 days to 5.3 days.
"The most significant advantage of this test is that it can be done at the bedside with immediate results available," said Professor John Sanderson, Professor of Medicine and Therapeutics, The Chinese University of Hong Kong. "This allows us to concentrate the resources on those who do have a cardiac problem. By checking everybody with chest pain in this way we hope that no patients with an impending heart attack are sent home because their pain is not typical or the ECG does not show any new changes"
This new method will provide a more rapid assessment of patients with
chest pain to identify those who need prompt life-saving treatment.
Professor Sanderson advises those people with chest pain should have a
check as soon as possible. If delay they will miss the opportunity
to have their coronary artery blockage treated and more heart muscle will
be damaged with possible fatal consequences.